Why study thermodynamics?

Thermodynamics is essentially the study of the internal motions of many body systems. Virtually all substances which we encounter in everyday life are many body systems of some sort or other (e.g., solids, liquids, gases, and light). Not surprisingly, therefore, thermodynamics is a discipline with an exceptionally wide range of applicability. Thermodynamics is certainly the most ubiquitous subfield of Physics outside Physics Departments. Engineers, Chemists, and Material Scientists do not study relatively or particle physics, but thermodynamics is an integral, and very important, part of their degree courses.

Many people are drawn to Physics because they want to understand why the world around us is like it is. For instance, why the sky is blue, why raindrops are spherical, why we do not fall through the floor, etc. It turns out that statistical thermodynamics can explain more things about the world around us than all of the other physical theories studied in the undergraduate Physics curriculum put together. For instance, in this course we shall explain why heat flows from hot to cold bodies, why the air becomes thinner and colder at higher altitudes, why the Sun appears yellow whereas colder stars appear red and hotter stars appear bluish-white, why it is impossible to measure a temperature below -273$^\circ$ centigrade, why there is a maximum theoretical efficiency of a power generation unit which can never be exceeded no matter what the design, why high mass stars must ultimately collapse to form black-holes, and much more!